Modeling with Equations Math Example 3

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Example 3

easy
Write an equation: 'A number doubled and increased by 7 equals 25.'

Solution

  1. 1
    Let nn be the number: 2n+7=252n + 7 = 25.
  2. 2
    Solve: 2n=182n = 18, n=9n = 9.

Answer

2n+7=25;n=92n + 7 = 25; \quad n = 9
Translating words to equations: 'doubled' means 2n2n, 'increased by 7' means +7+7, 'equals' means ==.

About Modeling with Equations

Translating a real-world situation into one or more equations that capture its mathematical relationships and constraints.

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More Modeling with Equations Examples

Example 1 easy

A phone plan costs [formula]0.10 per text. Write an equation for the monthly cost [formula] if you s

Example 2 medium

Two trains leave the same station traveling in opposite directions at 50 mph and 70 mph. After how m

Example 4 hard

The sum of three consecutive integers is 72. Find them.

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